zerg Mutalisk rush

First of all, employing the tactic of  Zerg Mutalisk Rush against the Terran is the least effective any mutalisk rush could ever be most especially against the Marines. However, against any Zerg player or any Protoss player, you have a big change to toppling down any enemy while they are on early expansion.  Word of advice, if you already have your Mutalisks ready, go ahead and attack your enemy immediately.  But before that, you need to expand really quickly and build your Mutalisks while building Zerglings to harrass your opponent. In other words, you should be saving your gas for the mutas later on.  And once you have enough gas quickly upgrade to lair but then again just make sure you are running both of the extractors while consuming your gas for the quick upgrade. Then at the same time, pump out your zerglings to harrass your enemy. Once you have finished upgrading to Lair, build your spire behind your minerals so your opponent will not be able to see it then when that is finished, build as many mutalisks as you can. After which, send them to the back of your enemy base camp where the workers are located. Destroy as many workers as your mutalisks can. That way, you can squeeze out and topple down and minimize your opponent’s economy. And you may turn to your roaches or hydralisks to completey defeat them. Now if your enemy is doing the same thing, it now becomes the race for the mutalisks, so build out quickly, then attack as soon as you have enough mutalisks, perhaps using the zergling rush as well.